Glue classes proposal 0.9
Joseph D. Darcy
Joe.Darcy at Sun.COM
Sat Mar 21 19:28:35 PDT 2009
From this proposal, I do not understand what you are trying to propose.
-Joe
Marek Kozieł wrote:
> AUTHOR: Lasu aka Marek Kozieł
>
> OVERVIEW
>
> FEATURE SUMMARY:
> Glue classes allow to link utils direct with objects.
>
> MAJOR ADVANTAGE:
> + Forgotten functionality can be not such big deal now.
>
> MAJOR BENEFIT(s):
> + New functions can be easy localized (critically important while introduce
> new peoples into project).
> + Security: glue class do not see anything protected.
> + Light binding new functions with existing classes.
> + Number of used classes reduction.
> + Allow to assign methods and functions(static methods) to arrays, classes,
> interfaces, …
> + It's proof against same method occurs in class and delegator as well like
> in two delegators.
> + Allow to link gained(.jar) logic with new one, witch is impossible before
> final developer implements his classes.
> + Allow to project compact interfaces and do not worry about additional
> logic.
>
>
> MAJOR DISADVANTAGE:
> Do not know any ;) sorry.
>
> ALTERNATIVES:
> Utils classes, more work on project, duplicated code...
>
>
> EXAMPLES
>
> SIMPLE EXAMPLE:
>
>
> Now time:
> public class base {
>
> public static <T> T[] flatten(T[][] this) {
> int length = 0;
> for (T[] subArray : this) {
> length += subArray.length;
> }
> T[] ret = (T[])
> Array.newInstance(this.getClass().getComponentType().getComponentType(),
> length);
> int pos = 0;
> for (T[] subArray : this) {
> System.arraycopy(subArray, 0, ret, pos, subArray.length);
> pos += subArray.length;
> }
> return ret;
> }
>
> }
> Now time(usage):
> public static void main(String[] args) {
> Integer[][] array = new Integer[][] { { 1, 2, 3, 4 }, { 5, 6, 7 }, {}, {
> 9, 0 } };
> System.out.println(Arrays.toString(base.flatten(array)));
> }
>
> Glue:
> public class base<T> glue( T[][] ) {
>
> public glue T[] flatten( this) {
> int length = 0;
> for (T[] subArray : this) {
> length += subArray.length;
> }
> T[] ret = (T[])
> Array.newInstance(this.getClass().getComponentType().getComponentType(),
> length);
> int pos = 0;
> for (T[] subArray : this) {
> System.arraycopy(subArray, 0, ret, pos, subArray.length);
> pos += subArray.length;
> }
> return ret;
> }
>
> }
> Glue(usage):
> public static void main(String[] args) {
> Integer[][] array = new Integer[][] { { 1, 2, 3, 4 }, { 5, 6, 7 }, {}, {
> 9, 0 } };
> System.out.println(array..flatten()..toString());
> }
>
> ADVANCED EXAMPLE:
> Now time:
> public class base {
>
> public static <T> int addAll( ArrayList<T> this, Iterator<? extends T>
> iterator) {
> int added = 0;
> while (iterator.hasNext()) {
> added += this.add(iterator.next()) ? 1 : 0;
> }
> return added;
> }
>
> public static <T, E extends T> int addAll(ArrayList<T> this, E[] elements)
> {
> int added = 0;
> for (T t : elements) {
> added += this.add(t) ? 1 : 0;
> }
> return added;
> }
>
> }
> Now time(usage):
> public static void main(String[] args) {
> Integer[] add = new Integer[] { 1, 2, 34, 2, 5, };
> ArrayList<Integer> arrayList = new ArrayList<Integer>();
> ArrayList<Integer> finall = new ArrayList<Integer>();
>
> base.addAll(arrayList, add);
> base.addAll(finall, add);
> base.addAll(finall,arrayList.iterator());
>
> System.out.println(finall);
> }
>
> Glue:
> public class base<T> glue( ArrayList<T> ){
>
> public glue int addAll( this, Iterator<? extends T> iterator) {
> int added = 0;
> while (iterator.hasNext()) {
> added += this.add(iterator.next()) ? 1 : 0;
> }
> return added;
> }
>
> public glue <E extends T> int addAll( this, E[] elements) {
> int added = 0;
> for (T t : elements) {
> added += this.add(t) ? 1 : 0;
> }
> return added;
> }
>
> }
> Glue(usage):
> public static void main(String[] args) {
> Integer[] add = new Integer[] { 1, 2, 34, 2, 5, };
> ArrayList<Integer> arrayList = new ArrayList<Integer>();
> ArrayList<Integer> finall = new ArrayList<Integer>();
>
> arrayList..addAll(add);
> finall..addAll(add);
> finall..addAll(arrayList.iterator());
>
> System.out.println(finall);
> }
>
> Glue second:
> public class base glue( Date )
> {
> private static final SimpleDateFormat sdf = new
> SimpleDateFormat("yyyy.MM.dd");
>
> public glue String format( this ) {
> synchronized (sdf) {
> return sdf.format(this);
> }
> }
>
> private static final Date applicationStart = new Date();
>
> public static glue Date applicationStart() {
> return applicationStart;
> }
> }
> Glue second(usage):
> public static void main(String[] args) {
> System.out.println(Date..applicationStart()..format());
> }
> DETAILS
>
> SPECIFICATION:
> JLS 8.8:
> ClassDeclaration:
> NormalClassDeclaration
> GlueClassDeclaration
> EnumDeclaration
>
> GlueClassDeclaration
> ClassModifiers_opt class Identifier TypeParameters_opt glue (
> GlueFormalParameter ) GlueClassBody
>
> GlueFormalParameter
> VariableModifiers Type
>
> GlueClassBody:
> { GlueClassBodyDeclarations_opt }
>
> GlueClassBodyDeclarations:
> GlueClassBodyDeclaration
> GlueClassBodyDeclarations GlueClassBodyDeclaration
>
> GlueClassBodyDeclaration:
> GlueClassMemberDeclaration
> StaticInitializer
>
> GlueClassMemberDeclaration:
> FieldDeclaration
> StaticMethodDeclaration
> GlueMethodDeclaration
> StaticClassDeclaration
> InterfaceDeclaration
> ;
>
> GlueMethodDeclaration:
> GlueMethodHeader MethodBody
>
> GlueMethodHeader:
> MethodModifiers_opt glue TypeParameters*opt ResultType
> GlueMethodDeclarator Throwsopt
>
> GlueMethodDeclarator:
> Identifier ( this,*opt FormalParameterListopt )
>
> *opt: 'this' occurs always and only if glue method is not static.
>
> TypeParameters from GlueClassDeclaration are always visible for
> TypeParameters in GlueMethodHeader (even if method is static).
>
>
> 15.12 Method Invocation Expressions:
>
> GlueMethodInvocation:<br />
> Primary .. NonWildTypeArguments*_opt TypeName_opt GlueMethodIdentifier (
> ArgumentList_opt )<br />
> super .. NonWildTypeArguments*_opt GlueMethodIdentifier ( ArgumentList_opt
> )<br />
> ClassName . super .. NonWildTypeArguments*_opt GlueMethodIdentifier (
> ArgumentList_opt )<br />
> TypeName .. NonWildTypeArguments* GlueMethodIdentifier ( ArgumentList_opt
> )<br /><br />
>
> NonWildTypeArguments* suit TypeParameters in GlueMethodHeader.<br /><br />
>
>
>
>
>
>
>
> COMPILATION:
> If object (except null) is valid for GlueFormalParameter then glue-method
> can be called for this object.
> If type is compatible with GlueFormalParameter then static glue-method can
> be called for this type.
> For non static methods glued-object is passed as first 'this' parameter.
> Compiled method signature contains TypeParameters from GlueClassDeclaration
> (at start), and it's always static.
>
>
> TESTING:
> Like simple static methods.
>
> LIBRARY SUPPORT:
> No.
>
> REFLECTIVE APIS:
> No.
>
> OTHER CHANGES:
> No.
>
> MIGRATION:
> None.
>
> COMPATIBILITY
> New jars are fully compatible. Code is only backward compatible.
>
> REFERENCES
>
> Glue classes proposal 0.9 :
> http://lasu2string.blogspot.com/2009/03/glue-classes-proposal-09.html
>
> Bug: Extension of 'Interface' definition to include class (static) methods:
> http://bugs.sun.com/view_bug.do?bug_id=4093687
>
>
>
>
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